Advice for a second playthrough?

I finished this masterpiece a few days ago with the high honour ending. While I do find John cool (and I appreciate him for going after Micah), I miss Arthur. So now I want to start a low honour run.

Towards the end I focused mainly on story missions because I wanted to see what happens so badly. Now that I know, this time I will do it slowly, as I bet I missed a lot of side missions and interactions. I am not the completionist type so I don't care about achievements, but I want to find stuff like the dinosaur bones and cigarette cards. Also figure out what's with the dismantled bodies that I've seen twice so far. I was a pretty lawful cowboy outside of the missions so now I will rob more people. The hardest part is probably going to be acting mean to everyone, haha. How did everyone's experiences go when playing for the second time and do you have any tips?